Technical Field
The technical field relates to a printing device, and more particularly, to a three-dimensional printing device.
Description of Related Art
As technology has advanced in recent years, many different methods that utilize additive manufacturing technology such as layer-by-layer model construction to build three-dimensional (3D) physical models have been proposed. Typically, the additive manufacturing technology is to convert design data of a 3D model, which is constructed by software such as computer-aided design (CAD), into multiple thin (quasi-two-dimensional) cross-sectional layers that are stacked in sequence. In the meantime, many technical means for forming multiple thin cross-sectional layers have also been proposed. For example, a printing unit of a three-dimensional printing device is configured to move above a printing bed along an X-Y plane according to spatial coordinates XYZ constructed according to the design data of the 3D model, so as to form a construction material into correct shapes of cross-sectional layers. Then, the printing unit is driven to move along the Z-axis layer-by-layer so that multiple cross-sectional layers are gradually stacked, and while the layers are cured layer-by-layer, a three-dimensional object is formed.
Generally, the printing unit is assembled on a carrying unit, and a driving unit is used for driving the carrying unit to facilitate movement of the printing unit in a printing space. Moreover, some printing units that carry materials require a plurality of driving units in order to increase load-carrying capacity. However, the driving units respectively use motors to drive the carrying unit to move between a plurality of screw rods, so that during the movement, tolerances or motor speed differences are generated due to sizes of the screw rods. Consequently, as time passes, a cumulative movement deviation is generated between the driving units, which causes imbalance and skew of the carrying unit. Therefore, it is necessary to provide a measure for correcting possible skew occurring during movement before a normal three-dimensional printing operation.